Sighting devices have been known for long time, most of which include a reticle or aiming point, the image of which is collimated with a collimating lens or a concave mirror and projected toward the eye of the viewer along parallel paths. Such collimating sights are advantageous for short range shooting where no magnification is needed, because the image of the reticle is projected out to an infinite point in space and is therefore always on target. Such sights also eliminate parallax with the result that the reticle image stays on the target even if the viewer moves his head. The main disadvantage of such configurations is a very small field of view, left for the shooter to detect the aiming point. It is even worth in case of a hand held pistol, where the hand movement make a very large bowing angle with respect to the shooter line of sight.
The collimating sights of the prior art are of two general types, both of which are designed for use with a generally short eye relief, and therefore, are usually mounted on the receiver portion of a rifle or a shotgun in close proximity to the eye of the shooter. The first general type of collimator sight of the prior art is disclosed in U.S. Pat. No. 1,442,015, issued in 1919 to E. D. Tillyer. This type of sight includes a collimated reticle within a tube about one to two inches in diameter, with the front end of the tube being opaque. As a result, the sight blocks most, or all, of the target from the field of view of the sighting eye of the shooter, and the sight must be used while both eyes of the shooter are open. Thus, the shooter sees the reticle of the sight with one eye and the target with the other eye and must rely on his own binocular ability to superimpose the two images. When a person uses a sight of this type where one eye looks at the reticle and the other eye looks at the field, the phenomenon of exophoria (the deviation of the visual axis of one eye away from that of the other eye in the absence of visual fusional stimuli) tends to frustrate the effort by causing the reticle image to drift over the field image, or to disappear altogether. Exophoria is a latent inability of one eye to attain binocular vision with the other eye because of imbalance of the extrinsic eye muscles, whereby the visual axes tend outward toward the temple. Thus, the first general type of collimated sights are difficult (if not impossible) to use, except for very quick snap shooting.
However, these sights are collimated and from their nature, when the user rotates his hand with the pistol and the sight on it, in a small angle, the reticule will disappear. The angle from which the shooter can still see the reticle is known to be the Maximum Noticeable Angle (MNA) of the sight.
Firearms, particularly hand-held fire arms are conventionally aimed by using a sight installed on the firearm and pointing the sight to the target point. By “target” is meant the object or person that the shooter intends to hit, and by “target point” is meant the point of the target at which the shooter aims the projectile.
Generally the projectiles may hit any point within an area about the target point. When the sight is aligned, it defines an aim line, and when said aim line passes through the shooter's aiming eye, the axis of the fire arm barrel should be substantially directed to the target point.
The accuracy of hand-held guns greatly depends on the relative orientation between the aiming line of the shooter's eye and the central axis of the gun's barrel. Since the aiming line coincides with the shooter's eye and with the target, in order to hit the target accurately, the aiming line and the central axis of the gun's barrel must be parallel. Otherwise, the bullet may deflect from the target's center.
Since any sight is mounted on top of the gun's slide, in most cases it is not perfectly aligned due to manufacturing and assembly tolerances. Therefore, it should contain an alignment mechanism, which can adjust its orientation with respect to the slide. Generally, the existing mechanisms are complex and expensive due to several alignment mechanical parts needed. Another problem arises when the shooter views the optical indication that is displayed when the sight is aligned. In many cases, the optical indication is an image of an optical fiber, which collects and transmits light to its proximal end (closer to the shooter's eye) and displays an illuminated dot. However, sometimes this dot is not sufficiently large and therefore, it is more difficult to the shooter to have a clear indication when exactly to shoot.
It is therefore, an object of this invention to provide a non-collimating sight for use with a firearm, or the like, which can be used by a shooter with either one eye or both eyes open.
It is a further object of this invention to provide a sight which is sufficiently small, so as not to obscure the target when the sight is used with only one eye of the shooter open thus making it possible to shoot with one eye or two.
It is still another object of this invention to provide a much shorter sight compare to the same reticle size, as in the prior art.
It is yet another object of this invention to provide a sight of the character described which is durable, inexpensive to manufacture, of simple construction, and yet reliable for short range shooting.
It is therefore needed to provide a simpler and more efficient mechanism, which includes only few moving parts. This is an additional object of the present invention—to provide such mechanism that is simple and that can be easily adjusted to obtain the desired alignment.
A further object is to provide a sight with a simple and reliable mechanism that allows a shooter to adjust the size of the image displayed by the optical fiber.
Other purposes and advantages of the invention will appear as the description proceeds.